import java.util.Scanner;

/**
 * Created by asus on 2017/10/12.
 */
public class Postfix {
    public static void main(String[] args) {
        String expression,again;
        int result;
        try{
            Scanner in = new Scanner(System.in);
            do {
                PostfixEvaluator evaluator = new PostfixEvaluator();
                System.out.println("Enter a valid postfix expression: ");
                expression = in.nextLine();
                result = evaluator.evaluate(expression);
                System.out.println();
                System.out.println("That expression equals"+result);
                System.out.print("Evaluate another expression [Y/N]?");
                again = in.nextLine();
                System.out.println();
            }
            while (again.equalsIgnoreCase("y"));
        }
        catch (Exception IOException){
            System.out.println("Input exception reportted");
        }
    }
}
